There is little relief in sight. At zero percent containment, the fire in Apache County has become the nation's No. 1 firefighting priority.

"It's touch-and-go," said Eric Neitzel, spokesman for the Show Low, Ariz., fire department. He said about 2,500 firefighters from around the country are trying to keep the fire, second-largest in state history, from consuming the towns in its path.

About 600 homes are threatened as the fire moves east toward New Mexico, he said.

A mandatory evacuation order was extended to remaining residents of Springerville and Eager in the path of the wildfire. About 7,000 people live in the two towns and surrounding areas, although many had already left.

The blaze is headed toward a pair of transmission lines that supply electricity to people as far east as Texas. El Paso Electric warned 372,000 customers of rolling blackouts if the fire damages power lines.

The enemy right now is heavy smoke that has blown as far east as Iowa and disrupted air travel to Albuquerque, 200 miles away. Thick ash has been falling in some towns from the fire, which started May 29.

The Apache County Public Health Services issued an air quality warning.

At the White Mountain Regional Medical Center, the number of people going to the emergency room with respiratory ailments has tripled from an average of two people a day to six, CEO Jerry Campeau said.

"It's the biggest risk now, aside from the risk to property," he said.

On a clear day, Campeau said, he can see the mountains 5 miles from the hospital. On Wednesday, visibility was about a half-mile. The hospital had to ground its helicopter because of the smoke, he said.

Ruben Irigoyen, 40, a chef, packed up his wife and three children and left Eagar on Monday because the fire was too close and the smoke too thick.

"We couldn't breathe," he said. "It was inside the house."

He said it was particularly bad for Alex, 7, who has allergies and respiratory problems.

The family was staying at a Red Cross shelter at a high school in the Pinetop-Lakeside area, 47 miles away. Irigoyen said he was tracking the fire's path on maps.

"I'm really concerned," he said, "because the maps are showing that the fire right now is where my house is."

Contributing: Associated Press

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